import math

def fibonacci_spiral():
    fibonacci_numbers = [1, 1]
    for i in range(2, 50):
        fibonacci_numbers.append(fibonacci_numbers[i - 1] + fibonacci_numbers[i - 2])

    total_length = 0
    previous_length = 0

    print(f"{'步数':<6}{'弧长':<20}{'与上一步的比值'}")
    print("-" * 50)

    for step in range(1, 51):
        radius = fibonacci_numbers[step - 1]
        arc_length = (90 / 360) * 2 * math.pi * radius

        total_length += arc_length

        if step == 1:
            ratio = "N/A"
        else:
            ratio = arc_length / previous_length

        print(f"{step:<6}{arc_length:<20.6f}{ratio}")

        previous_length = arc_length

    print("-" * 50)
    print(f"总弧长: {total_length:.6f}")

fibonacci_spiral()